It's debatable, but I always assumed his mechanical hand just took the pain so to speak, but later EU and the Prequels established that Sith and Jedi could use the force to repel blaster fire without the use of a Lightsaber

There are multiple theories. Most have been mentioned here. His artificial hand being made out of Mandalorian Iron etc, or him using the Force.

Just bare in mind that, in 1980, computer techniques weren't as good as they are now. We'll probably never know.
Same goes for the 'who shot first' debate that was caused by a lack of good computer technology as well (Greedo shot first!!)

also to add to Ztalkers post, in 1980 a lot of what we know of the force, force powers and Vader's suit weren't created or at least explained by GL, so at the time it was probably just "Because it looked cool" but now we have all the guides and books to explain other possibilities

The concept of using the Force to simply block laser fire is such an idiotically cheap-assed copout that I'm not even going to consider it as a possibility, because (among other things) there's too many instances where a Jedi or Sith could have been saved by it to say that Vader was apparently the only person who could do it. And as mentioned above, the idea of such a power is a copout. Besides, if Vader "absorbed" the bolts, then they wouldn't have exploded against his hand like they do when they hit walls, nor would Vader's hands be smoking as he catches the gun and puts it down. The armor on his suit is what protected him.

"There is something going on in time and space, and beyond time and space, which, whether we like it or not, spells duty." -Winston Churchill

"For of all sad words of tongue or pen, The saddest are these: 'It might have been!'" -John Whittier

Well, just because "you can" do something without a lightsaber does not mean that its better. I can spread peanutbutter on my toast with my finger rather than a butter knife, but I would much prefer the butterknife than a finger.

Just as your gf would prefer your somethingelse rather than your finger... (hopefully)

Outside of the continuity, I'm sure it was added because it was visually cool and to establish that Han (while awesome) was in a completely different league than Vader. It was just another way to show how bad Vader was.

Within the context of the story, I think it was probably the force. If it had been armor, the blast would have burned through the outer glove, which I don't think it did. I think it was the force, and likely something that only came from the Chosen One.

Again, though, the real reason it was added is because it was just some cool **** to see.

I think that Vader used the force because he only has one hand that had the Mandalorian Gauntlet. but he deflects the shots with his right hand, then on with his left, then force pulls Han's blaster with his right. So if it is his armour, then I would think he only would use his right hand, the one with the Special Gauntlet, then force pull the gun with his left. So I think from the get-go he is just using the force and toying with Han.

Really just shows how bad ass Vader is and that Han really has zero chance of doing anything.

ps- let me know if I have that mandalorian Gauntlet thing wrong, maybe both his hands had gauntlets. I forget.

Even in the OT (not considering the prequels at all), Vader's right arm is robotic, we know for a fact. If we take the ROTJ visual "skeleton" glow as some kind of guide, apparently both his hands are robotic (even if his right arm is mostly real). But if you watch the scene frame by frame, he blocks it with both hands, and some of the shots hit his glove and disappear in a puff of smoke/sparks, while others bounce off and hit the walls. Maybe some combination of force and physical blocking?

I don't know about this "Mandalorian gauntlet" thing of course, having washed my hands of the EU stuff long ago (other than the PC games). It appears he's just wearing leather gloves over his robot hands.

I sort of assumed for the longest time it was just that Vader's armor protects him. But then when you consider that the suit appears to be mostly leather (not even the kind of full coverage offered by the "useless" Stormtrooper armor; please note that Vader's shoulder armor deflects a lightsaber blow from Luke in ESB!), I guess you might say it was some kind of Force ability he used (going just by the movies here, since the EU will tell you whatever).

I think stylistically it was just meant to show that Vader was more dangerous than the average bad guy, and show why the good guys couldn't just gun him down.

I suppose having it be a "force powered block" would further emphasize that Solo is in over his head (remember, this is the guy who poo-pooed the Jedi and the Force in the previous movie), where his simple, naturalistic, technology-based methods of fighting aren't adequate for this situation. He's dealing with the Dark Lord of the Sith, now.

I agree. I've pretty much learned to ignore the EU retcons that conveniently explain everything away, usually in the stupidest fashion imaginable, and are therefore essentially BS, IMO.

I came to the conclusion that he was using the Force a long time ago for the very reason that you just stated. In the first film, we see how Han gets out of a compromising position by shooting first, but this is Han's first encounter with an enemy Force-user in the films and he and the audience get a demonstration of just how useless his methods really are against one when he tries the same thing against Vader.

This is just one example of how the idiotic revisionism on the part of Lucasfilm and the EU is compromising and even destroying the integrity of the OT.

"They should rename the team to the Washington Government Sucks. Put Obama on the helmet. Line the entire walls of the stadium with the actual text of the ACA.

Fix their home team score on the board to the debt clock, they can win every game 17,000,000,000,000 to 24. Losing team gets taxed by the IRS 100%, then droned."

I go with his hand. It didn't reflect and fly somewhere else, did it?
I can't remember and I really can't be bothered in watching the movie just for that....

i don't remenber that happening either...? i think it was a mechanichle device. i mean, if he used the force it would have hit somewhere else.
plus, negate energy wasn't even thought up untill after the movie was made

I always thought he was using the force, but who knows until Lucas says one way or the other. And even then, that would open up a whole can of worms and people still wouldn't agree. At any rate, it's one of my favorite moments in the OT.

Then again Vader's suit was heavily armored, he was able to take that hit on the shoulder from Luke's lightsaber, so maybe his armor was able to deflect blaster shots.